Rated 5 out of 5 stars

It's IMPORTANT TO DEACTIVATE "size" criteria. Because it's funny but it seems that duplicates are not exact copies. This means that if you choose "size" this great extension won't find duplicates. But if you deactivate that option, it seems to work great! Thanks to kevbroch, I think the author should include this in the description or add something to the extension, to explain that issue... It's a great extension! Works fine on Thunderbird 3 portable under Windows 7 64 bits...

This review is for a previous version of the add-on (0.3.3).